Cells, a few additional comments

[KTribe]

Ingestion by the cells is usually accomplished by
active transport.
Food molecules are made into cellular fuel(ATP)by
cellular respiration. When oxygen is used, it is
called aerobic cellular respiration and while it is
true that the majority of our cells use this energy
pathway, some cells, such as muscle cells can switch
to anaerobic cellular respiration (fermentation) under
conditions of oxygen debt.
Cellular respiration, especially the aerobic kind
relies heavily on coenzymes (the precursors are the B
vitamins) and dozens of enzymes, all of which are
genetically determined.

Luckily, gases such as ozygen and carbon dioxide
diffuse easily out of cells and the cells do not need
to supply any energy for this to happen.
Excretion is accomplished by a process known as active
transport, or exocytosis to be more exact. The cells
must expend energy (use ATP) in order for this to
happen. Excretion by the cells are profoundly
influenced by intracellular and extracellular solute
concentrations.

d) Excitability & conductivity:

Excitability and conductivity rely on a host of
factors. With excitability, cells rely on a great
assemlage of proteins, from neurotransmitters to
contractile proteins, as well as the presences of cell
receptors. There are also solute contentrations
involved, especially those of sodium, potassium and
calcium. Secretion is the production of a non-living,
non-supported cellular products, whether it's sweat or
hormones or enzymes, all must be released via
exocytosis.
Homeostasis is one of the most complex and poorly
understood functions of the body. All living organisms
perform it at all levels, from the cellular level, on
up. While homeostasis primarily relies on the nervous
and endocrine systems, ALL organ systems, all cells,
are involved, and it doesn't matter if you are an
amobea or a plant.

Every cell has ability to

Yes and no. It would be more accurate to say that MOST
cells have the ability to reproduce. Some cells tend
to leave the cell cycle and not reproduce again (like
nerve cells, although stem cell research is changing
that)or they remain stuck in the G1 phase of the cell
cycle and are unlikely to reproduce unless triggered
to do so, cardiac mucle and liver cells are good
examples.
Distrubance of the code happens much more than you
think. One does not prance on the planet for any
significant amount of time without mutations arising.
Fortunately, most mutations are neutral,and are often
repaired immediately by over 50 DNA repair enzymes,
which means there is little or no phenotypic effects.
Because of the redunancy of the genetic code, this
tend to lessen the effects of many point mutations.
Harmful changes can result in anything from faulty
cell transport proteins to the lack of necessary
enzymes. Harmful changes that disturb the biochemical
controls of the cell cycle result in cancer.
Up until recently, it was assumed that there must be
at least 100,000 gemes in humans because of the "One
gene, one polypeptide theory", unfortunately, the
results of the Human Genome Project has blown that
theory away. We only have a little over 30,000 genes,
which means the genes may express different proteins
under different circumstances and environments. I
believe that this finding is one of the most
significant of the recent discoveries in the field of
genetics.
A significant amount of our DNA are actually exons,
non-coding segments; there are many theories regarding
the function of exons. Mutations that occur in
non-coding DNA segments would have no harmful effects
unless the reading frame is shifted as a result, or
breakage of the chromosome occurs.

Now, since I teach Genetics and Cytology at the
college level, you would think I wouldn't be such a
big believer in homeopathy, but to the contrary, I am
fascinated by the homeopathic explanation of disease
and the effects on the body and I have come to the
conclusion that recent advances in scientific
knowledge will only prove that homeopathy is light
years ahead of what we call traditional science!
Thousands of years ago, Yoga made the connection
between the mind and the body, while "modern medicine"
has only recently made the same connection. Energy
transformations are the basis of life, so it only
makes sense that energy-based medicine works!

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